Art Ensemble and Mary Halvorson among the hair-raising turns at Berlin Fest humdinger

The English music critic Richard Williams finished his three-year stint as Jazzfest Berlin's artistic director, handing the controls over to Nadin Deventer, who proceeded to boldly throw down her gauntlet for this and her next two festivals. She has extensive programming experience, and had been working as production head for the previous two years. Deventer's main mark is made by firstly condensing the festival down to a hardcore four days, jettisoning the run-up gigs of previous years, and secondly, by opening up the entire potential space of the Berliner Festspiele edifice, from its main stage down to its basement underworld. She also transformed the entrance café into a venue, and utilised the foyer space on the upper level, as well as continuing to use satellite locations such as Quasimodo and the A-Trane jazz club.

The Grand Opening night operated a seven-hour timetable with multiple choices, which might have been frustrating on one level, but also magnified the vitality of the evening, with cross-current crowds and extreme musical contrasts. Two of the strongest themes involved artists identified with Chicago (even if many of them eventually fled to NYC), and a heavy number of sets revolving around individualist guitarists.

Two of the key Windy City combos appeared in 'special edition' Berliner fusion guises. The Art Ensemble of Chicago line-up was quite possibly the largest seen so far, with Roscoe Mitchell spending much of his time conducting forces that included a strong string quotient, sensibly dignified. Unfortunately, much of the AEC character from olden days is now lost. There is little in the way of ritualistic, Afro-improvisation, preening display and wily humour, or indeed free jazz or trad jazz content. Positively speaking, this meant increased unpredictability, and a desire to shape a different sound, but this was at the expense of any charismatic abandon or sonic extremity. The best stretch came courtesy of the splinter group featuring almost-founder percussionist Famoudou Don Moye (pictured), Dudu Kouate (Afro-drums), Hugh Ragin (trumpet) and Jaribu Shahid (bass).

Trumpeter Jaimie Branch delivered a lacklustre set during the Austrian Saalfelden fest in August, but here, her Fly Or Die quartet were fuelled by the energy of their leader, who managed to exude supreme casualness, while repeatedly spouting concise bursts of solo lava, goading drummer Chad Taylor into manic triphammer beat-skipping. She swapped between mute crisp and open frazzle, distant microphone or bell-closeness.

Fellow trumpeter Rob Mazurek's Exploding Star International added six Berlin players to the nine Americans, having the guts to maintain spacious minimalism for quite a lengthy spell, but then eventually aroused to an intense pitch of power. Damon Locks impressed, with his scholarly office worker vibe, intoning texts into his vintage telephone, doctoring via electronics. Taylor was on board again and eventually rolled crazily, while Mazurek and Branch worked together with the spicy pepper-spraying. Mazurek blew into his tangle of modular wiring, as Lock told of a "careening prism within" (or was that "prison"?).

Mazurek also played an atmospheric duo set with the young French guitarist Julien Desprez (pictured), who was the vital discovery of this festival, and deliverer of quite possibly its best set. The Berlin bass-and-drums team of Jean-Francois Riffaud and Max Andrzejewski drifted on, Mazurek departed, and the guitar trio Abacaxi was born. Literally, as this was their first gig anywhere. Distressed metallic contusions deified the abrupt, everyone had a sonic impediment, and the bright white flickershow lighting was manually controlled by the players. This might account for the borderline ridiculous tap-dancing routines around their crowded semi-circle of effects pedals, as a month's worth of compacted, nervy excitement was crammed into however many minutes they were speeding at full pelt, juddering, jolting and spasming as they demanded total attention to heavy detail. Go see them next time, for sure!

Away from the mainline, there were many innovative performances in other settings. Mary Halvorson played her first gig in a hair salon, in a duo with pedal-steel player Susan Alcorn. A quartet of Tomas Fujiwara (drums), Adrian Myhr (bass), Jacob Garchik (trombone) and Jon Irabagon (saxophones) delivered some good ole free jazz in a not-so-private apartment. Another discovery, the Canadian organist Kara-Lis Coverdale played solo on the gargantuan house instrument of the Kaiser Wilhelm Church, and the mysterious, masked Kim Collective ritualised down in the caverns under the main stage, arrayed in circular fashion, set up in individual alcoves that could have been specially designed for such sculpted surround-sound mystery. These are just selected outstanding examples of Jazzfest Berlin's spread, not only sonically, but also spatially.